This invention is generally related to a plant protection system that can be quickly and easily assembled in a field for protecting a crop of plants against adverse environmental conditions such as frost and freezing as well as insects or other pests. This invention has particular application to row crops such as strawberries and similar plants, but can be modified for other crops.
Cultivated crops have always been subject to the forces of nature and unseasonable climatic conditions such as frost or freezing can destroy a crop. Likewise, excessive or insufficient rainfall during the growing season can have a devastating effect on crops. Other natural threats such as insects are also a serious concern. Ideally, all these adverse conditions could be eliminated in a greenhouse enclosure, but that is obviously impossible and economically infeasible where thousands of acres are under cultivation.
In an attempt to replicate the benefits of a greenhouse but at a significantly reduced cost, several methods of covering crops in the field have evolved which involve draping a pliable cover such as plastic sheeting or other types of fabric over the crop to afford protection to the plants from external elements and propping up the pliable cover with a frame to keep it away from the plants. While this type of cover can be easily placed over a field of crops by unrolling across the field, if the cover touches the plants, their foliage, blossoms or fruit, damage can occur. This is commonly called “burn”.
Because of their flexibility and pliability, such covers will naturally sag between rigid frames, making it difficult to prevent touching the plant. While it may be possible to stretch a cover to eliminate sag, this is generally not feasible because of the large field areas involved and the difficulty in securing the perimeter of the cover. Adding more rigid frames to shorten the distance between frames will alleviate the problem of sag to some extent but then the cost begins to increase, defeating the intended purpose of providing protection to the plants in an economical way. It is apparent that the covers must be supported in two directions, with the rigid frame providing support in one direction and support between the frames in the other direction being provided by another means.